Turbulent structures in unsteady wall-bounded flow subject to temporal acceleration etc15 Tracking Number 335Presentation: Session: Wall-bounded flows 2 Room: Room M Session start: 15:00 Tue 25 Aug 2015 Zhixin Wang Zhixin.Wang@warwick.ac.uk Affifliation: Tariq Talha T.Talha.2@warwick.ac.uk Affifliation: Yongmann Chung Y.M.Chung@warwick.ac.uk Affifliation: Topics: - Wall bounded flows Abstract: Direct numerical simulations (DNS) of a transient turbulent channel flow subject to constant temporal acceleration have been performed with a final Reynolds number of $\Retau=800$. The response of turbulent structures to the temporal acceleration is investigated. A significant delay in the response of turbulent flow is observed in various turbulent properties. It is found that the response of turbulent flow to temporal acceleration consists of two stages: the destruction of the initial \emph{old} turbulence, followed by the generation of \emph{new} turbulence associated with a higher $Re$ number. The \emph{new} turbulence is much stronger than the \emph{old} turbulence. |